| Message ID | 0db6c314-1ef4-9bfa-1baa-7214dd2ee061@infradead.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [resend] uapi/linux/keyctl.h: don't use C++ reserved keyword as a struct member name | expand |
On Tue, Aug 28, 2018 at 04:34:04PM -0700, Randy Dunlap wrote: > From: Randy Dunlap <rdunlap@infradead.org> > > Since this header is in "include/uapi/linux/", apparently people > want to use it in userspace programs -- even in C++ ones. > However, the header uses a C++ reserved keyword ("private"), > so change that to "dh_private" instead to allow the header file > to be used in C++ userspace. > > Fixes https://bugzilla.kernel.org/show_bug.cgi?id=191051 > Fixes: ddbb41148724 ("KEYS: Add KEYCTL_DH_COMPUTE command") > > Signed-off-by: Randy Dunlap <rdunlap@infradead.org> > Cc: David Howells <dhowells@redhat.com> > Cc: James Morris <jmorris@namei.org> > Cc: "Serge E. Hallyn" <serge@hallyn.com> > Cc: keyrings@vger.kernel.org > Cc: linux-security-module@vger.kernel.org > Cc: Mat Martineau <mathew.j.martineau@linux.intel.com> > Cc: stable@vger.kernel.org > --- > include/uapi/linux/keyctl.h | 2 +- > security/keys/dh.c | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > > --- lnx-416.orig/include/uapi/linux/keyctl.h > +++ lnx-416/include/uapi/linux/keyctl.h > @@ -65,7 +65,7 @@ > > /* keyctl structures */ > struct keyctl_dh_params { > - __s32 private; > + __s32 dh_private; Ick ick ick, why not just put the C "namespace" on all uapi files if you are including them from c++ code? I'm sure this isn't the only problem that has this problem, right? This is valid C, no need to start worrying about C++ reserved names. thanks, greg "'struct class' is your friend" k-h
On Tue, 28 Aug 2018 19:42:24 -0700 Greg KH <gregkh@linuxfoundation.org> wrote: > > --- lnx-416.orig/include/uapi/linux/keyctl.h > > +++ lnx-416/include/uapi/linux/keyctl.h > > @@ -65,7 +65,7 @@ > > > > /* keyctl structures */ > > struct keyctl_dh_params { > > - __s32 private; > > + __s32 dh_private; > > Ick ick ick, why not just put the C "namespace" on all uapi files if you > are including them from c++ code? I'm sure this isn't the only problem > that has this problem, right? > > This is valid C, no need to start worrying about C++ reserved names. We've done this before and it's a simple enough change in order to be friendly toward others. That being said, it's been like this for two years so presumably anyone who is using this header from C++ is already `extern "C" { ...}' around their #include. I'm OK with the patch as-is, but if we run into this issue more often, we might want to look at doing something kernel-wide. I'm not sure what though. Adding #ifdef __cplusplus extern "C" { #endif ... #ifdef __cplusplus } #endif into every uapi file might work. Unpleasing.
On Tue, Aug 28, 2018 at 04:34:04PM -0700, Randy Dunlap wrote: > From: Randy Dunlap <rdunlap@infradead.org> > > Since this header is in "include/uapi/linux/", apparently people > want to use it in userspace programs -- even in C++ ones. > However, the header uses a C++ reserved keyword ("private"), > so change that to "dh_private" instead to allow the header file > to be used in C++ userspace. This change breaks all existing C programs that rely on <linux/keyctl.h> uapi header in order to get struct keyctl_dh_params definition, however. > > Fixes https://bugzilla.kernel.org/show_bug.cgi?id=191051 > Fixes: ddbb41148724 ("KEYS: Add KEYCTL_DH_COMPUTE command") > > Signed-off-by: Randy Dunlap <rdunlap@infradead.org> > Cc: David Howells <dhowells@redhat.com> > Cc: James Morris <jmorris@namei.org> > Cc: "Serge E. Hallyn" <serge@hallyn.com> > Cc: keyrings@vger.kernel.org > Cc: linux-security-module@vger.kernel.org > Cc: Mat Martineau <mathew.j.martineau@linux.intel.com> > Cc: stable@vger.kernel.org > --- > include/uapi/linux/keyctl.h | 2 +- > security/keys/dh.c | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > > --- lnx-416.orig/include/uapi/linux/keyctl.h > +++ lnx-416/include/uapi/linux/keyctl.h > @@ -65,7 +65,7 @@ > > /* keyctl structures */ > struct keyctl_dh_params { > - __s32 private; > + __s32 dh_private; > __s32 prime; > __s32 base; > }; > --- lnx-416.orig/security/keys/dh.c > +++ lnx-416/security/keys/dh.c > @@ -307,7 +307,7 @@ long __keyctl_dh_compute(struct keyctl_d > } > dh_inputs.g_size = dlen; > > - dlen = dh_data_from_key(pcopy.private, &dh_inputs.key); > + dlen = dh_data_from_key(pcopy.dh_private, &dh_inputs.key); > if (dlen < 0) { > ret = dlen; > goto out2; > >
On Mon, 10 Sep 2018 00:00:18 +0200 Eugene Syromiatnikov <esyr@redhat.com> wrote: > On Tue, Aug 28, 2018 at 04:34:04PM -0700, Randy Dunlap wrote: > > From: Randy Dunlap <rdunlap@infradead.org> > > > > Since this header is in "include/uapi/linux/", apparently people > > want to use it in userspace programs -- even in C++ ones. > > However, the header uses a C++ reserved keyword ("private"), > > so change that to "dh_private" instead to allow the header file > > to be used in C++ userspace. > > This change breaks all existing C programs that rely on <linux/keyctl.h> > uapi header in order to get struct keyctl_dh_params definition, however. Are there such programs? Do they reference the `private' field?
Andrew Morton <akpm@linux-foundation.org> wrote:
> Are there such programs? Do they reference the `private' field?
They would use the keyutils.h header from keyutils package probably. There
the field was named "priv" not "private". The kernel's UAPI header should be
amended again to match that.
David
--- lnx-416.orig/include/uapi/linux/keyctl.h +++ lnx-416/include/uapi/linux/keyctl.h @@ -65,7 +65,7 @@ /* keyctl structures */ struct keyctl_dh_params { - __s32 private; + __s32 dh_private; __s32 prime; __s32 base; }; --- lnx-416.orig/security/keys/dh.c +++ lnx-416/security/keys/dh.c @@ -307,7 +307,7 @@ long __keyctl_dh_compute(struct keyctl_d } dh_inputs.g_size = dlen; - dlen = dh_data_from_key(pcopy.private, &dh_inputs.key); + dlen = dh_data_from_key(pcopy.dh_private, &dh_inputs.key); if (dlen < 0) { ret = dlen; goto out2;